Fix stuck channel in ARI through the introduction of synchronous bridge actions.
[asterisk/asterisk.git] / res / res_calendar_exchange.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2008 - 2009, Digium, Inc.
5  *
6  * Terry Wilson <twilson@digium.com>
7  *
8  * See http://www.asterisk.org for more information about
9  * the Asterisk project. Please do not directly contact
10  * any of the maintainers of this project for assistance;
11  * the project provides a web site, mailing lists and IRC
12  * channels for your use.
13  *
14  * This program is free software, distributed under the terms of
15  * the GNU General Public License Version 2. See the LICENSE file
16  * at the top of the source tree.
17  */
18
19 /*! \file
20  * \brief Resource for handling MS Exchange calendars
21  */
22
23 /*** MODULEINFO
24         <depend>neon</depend>
25         <depend>ical</depend>
26         <depend>iksemel</depend>
27         <support_level>core</support_level>
28 ***/
29
30 #include "asterisk.h"
31
32 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
33
34 #include <libical/ical.h>
35 #include <ne_session.h>
36 #include <ne_uri.h>
37 #include <ne_request.h>
38 #include <ne_auth.h>
39 #include <ne_redirect.h>
40 #include <iksemel.h>
41
42 #include "asterisk/module.h"
43 #include "asterisk/channel.h"
44 #include "asterisk/calendar.h"
45 #include "asterisk/lock.h"
46 #include "asterisk/config.h"
47 #include "asterisk/astobj2.h"
48 #include "asterisk/uuid.h"
49
50 static void *exchangecal_load_calendar(void *data);
51 static void *unref_exchangecal(void *obj);
52 static int exchangecal_write_event(struct ast_calendar_event *event);
53
54 static struct ast_calendar_tech exchangecal_tech = {
55         .type = "exchange",
56         .description = "MS Exchange calendars",
57         .module = AST_MODULE,
58         .load_calendar = exchangecal_load_calendar,
59         .unref_calendar = unref_exchangecal,
60         .write_event = exchangecal_write_event,
61 };
62
63 struct exchangecal_pvt {
64         AST_DECLARE_STRING_FIELDS(
65                 AST_STRING_FIELD(url);
66                 AST_STRING_FIELD(user);
67                 AST_STRING_FIELD(secret);
68         );
69         struct ast_calendar *owner;
70         ne_uri uri;
71         ne_session *session;
72         struct ao2_container *events;
73 };
74
75 struct xmlstate {
76         char tag[80];
77         int in_response;
78         int in_propstat;
79         int in_prop;
80         void *ptr;
81         struct exchangecal_pvt *pvt;
82 };
83
84 static int parse_tag(void *data, char *name, char **atts, int type)
85 {
86         struct xmlstate *state = data;
87         char *tmp;
88
89         if ((tmp = strchr(name, ':'))) {
90                 tmp++;
91         } else {
92                 return IKS_HOOK;
93         }
94
95         ast_copy_string(state->tag, tmp, sizeof(state->tag));
96
97         switch (type) {
98         case IKS_OPEN:
99                 if (!strcasecmp(state->tag, "response")) {
100                         struct ast_calendar_event *event;
101
102                         state->in_response = 1;
103                         if (!(event = ast_calendar_event_alloc(state->pvt->owner))) {
104                                 return IKS_NOMEM;
105                         }
106                         state->ptr = event;
107                 } else if (!strcasecmp(state->tag, "propstat")) {
108                         state->in_propstat = 1;
109                 } else if (!strcasecmp(state->tag, "prop")) {
110                         state->in_prop = 1;
111                 }
112                 break;
113
114         case IKS_CLOSE:
115                 if (!strcasecmp(state->tag, "response")) {
116                         struct ao2_container *events = state->pvt->events;
117                         struct ast_calendar_event *event = state->ptr;
118
119                         state->in_response = 0;
120                         if (ast_strlen_zero(event->uid)) {
121                                 ast_log(LOG_ERROR, "This event has no UID, something has gone wrong\n");
122                                 event = ast_calendar_unref_event(event);
123                                 return IKS_HOOK;
124                         }
125                         ao2_link(events, event);
126                         event = ast_calendar_unref_event(event);
127                 } else if (!strcasecmp(state->tag, "propstat")) {
128                         state->in_propstat = 0;
129                 } else if (!strcasecmp(state->tag, "prop")) {
130                         state->in_prop = 0;
131                 }
132                 break;
133
134         default:
135                 return IKS_OK;
136         }
137
138         return IKS_OK;
139 }
140
141 static time_t mstime_to_time_t(char *mstime)
142 {
143         char *read, *write;
144         icaltimetype tt;
145         for (read = write = mstime; *read; read++) {
146                 if (*read == '.') {
147                         *write++ = 'Z';
148                         *write = '\0';
149                         break;
150                 }
151                 if (*read == '-' || *read == ':')
152                         continue;
153                 *write = *read;
154                 write++;
155         }
156
157         tt = icaltime_from_string(mstime);
158         return icaltime_as_timet(tt);
159 }
160
161 static enum ast_calendar_busy_state msbusy_to_bs(const char *msbusy)
162 {
163         if (!strcasecmp(msbusy, "FREE")) {
164                 return AST_CALENDAR_BS_FREE;
165         } else if (!strcasecmp(msbusy, "TENTATIVE")) {
166                 return AST_CALENDAR_BS_BUSY_TENTATIVE;
167         } else {
168                 return AST_CALENDAR_BS_BUSY;
169         }
170 }
171
172 static int parse_cdata(void *data, char *value, size_t len)
173 {
174         char *str;
175         struct xmlstate *state = data;
176         struct ast_calendar_event *event = state->ptr;
177
178
179         str = ast_skip_blanks(value);
180
181         if (str == value + len)
182                 return IKS_OK;
183
184         if (!(str = ast_calloc(1, len + 1))) {
185                 return IKS_NOMEM;
186         }
187         memcpy(str, value, len);
188         if (!(state->in_response && state->in_propstat && state->in_prop)) {
189                 ast_free(str);
190                 return IKS_OK;
191         }
192         /* We use ast_string_field_build here because libiksemel is parsing CDATA with &lt; as
193          * new elements which is a bit odd and shouldn't happen */
194         if (!strcasecmp(state->tag, "subject")) {
195                 ast_string_field_build(event, summary, "%s%s", event->summary, str);
196         } else if (!strcasecmp(state->tag, "location")) {
197                 ast_string_field_build(event, location, "%s%s", event->location, str);
198         } else if (!strcasecmp(state->tag, "uid")) {
199                 ast_string_field_build(event, uid, "%s%s", event->location, str);
200         } else if (!strcasecmp(state->tag, "organizer")) {
201                 ast_string_field_build(event, organizer, "%s%s", event->organizer, str);
202         } else if (!strcasecmp(state->tag, "textdescription")) {
203                 ast_string_field_build(event, description, "%s%s", event->description, str);
204         } else if (!strcasecmp(state->tag, "dtstart")) {
205                 event->start = mstime_to_time_t(str);
206         } else if (!strcasecmp(state->tag, "dtend")) {
207                 event->end = mstime_to_time_t(str);
208         } else if (!strcasecmp(state->tag, "busystatus")) {
209                 event->busy_state = msbusy_to_bs(str);
210         } else if (!strcasecmp(state->tag, "reminderoffset")) {
211                 /*XXX Currently we rely on event->start being set first which means we rely on the response order
212                  * which technically should be fine since the query returns in the order we ask for, but ... */
213                 event->alarm = event->start - atoi(str);
214         }
215
216         ast_free(str);
217         return IKS_OK;
218 }
219
220 static void exchangecal_destructor(void *obj)
221 {
222         struct exchangecal_pvt *pvt = obj;
223
224         ast_debug(1, "Destroying pvt for Exchange calendar %s\n", pvt->owner->name);
225         if (pvt->session) {
226                 ne_session_destroy(pvt->session);
227         }
228         ast_string_field_free_memory(pvt);
229
230         ao2_callback(pvt->events, OBJ_UNLINK | OBJ_NODATA | OBJ_MULTIPLE, NULL, NULL);
231
232         ao2_ref(pvt->events, -1);
233 }
234
235 static void *unref_exchangecal(void *obj)
236 {
237         struct exchangecal_pvt *pvt = obj;
238
239         ao2_ref(pvt, -1);
240         return NULL;
241 }
242
243 /* It is very important to use the return value of this function as a realloc could occur */
244 static struct ast_str *generate_exchange_uuid(struct ast_str *uid)
245 {
246         char buffer[AST_UUID_STR_LEN];
247
248         ast_uuid_generate_str(buffer, sizeof(buffer));
249         ast_str_set(&uid, 0, "%s", buffer);
250         return uid;
251 }
252
253 static int is_valid_uuid(struct ast_str *uid)
254 {
255         struct ast_uuid *uuid = ast_str_to_uuid(ast_str_buffer(uid));
256
257         if (uuid) {
258                 ast_free(uuid);
259                 return 1;
260         }
261
262         return 0;
263 }
264
265 static struct ast_str *xml_encode_str(struct ast_str *dst, const char *src)
266 {
267         const char *tmp;
268         char buf[7];
269
270         for (tmp = src; *tmp; tmp++) {
271                 switch (*tmp) {
272                 case '\"':
273                         strcpy(buf, "&quot;");
274                         break;
275
276                 case '\'':
277                         strcpy(buf, "&apos;");
278                         break;
279
280                 case '&':
281                         strcpy(buf, "&amp;");
282                         break;
283
284                 case '<':
285                         strcpy(buf, "&lt;");
286                         break;
287
288                 case '>':
289                         strcpy(buf, "&gt;");
290                         break;
291
292                 default:
293                         sprintf(buf, "%c", *tmp);
294                 }
295
296                 ast_str_append(&dst, 0, "%s", buf);
297         }
298
299         return dst;
300 }
301
302 static struct ast_str *epoch_to_exchange_time(struct ast_str *dst, time_t epoch)
303 {
304         icaltimezone *utc = icaltimezone_get_utc_timezone();
305         icaltimetype tt = icaltime_from_timet_with_zone(epoch, 0, utc);
306         char tmp[30];
307         int i;
308
309         ast_copy_string(tmp, icaltime_as_ical_string(tt), sizeof(tmp));
310         for (i = 0; tmp[i]; i++) {
311                 ast_str_append(&dst, 0, "%c", tmp[i]);
312                 if (i == 3 || i == 5)
313                         ast_str_append(&dst, 0, "%c", '-');
314                 if (i == 10 || i == 12)
315                         ast_str_append(&dst, 0, "%c", ':');
316                 if (i == 14)
317                         ast_str_append(&dst, 0, "%s", ".000");
318         }
319
320         return dst;
321 }
322
323 static struct ast_str *bs_to_exchange_bs(struct ast_str *dst, enum ast_calendar_busy_state bs)
324 {
325         switch (bs) {
326         case AST_CALENDAR_BS_BUSY:
327                 ast_str_set(&dst, 0, "%s", "BUSY");
328                 break;
329
330         case AST_CALENDAR_BS_BUSY_TENTATIVE:
331                 ast_str_set(&dst, 0, "%s", "TENTATIVE");
332                 break;
333
334         default:
335                 ast_str_set(&dst, 0, "%s", "FREE");
336         }
337
338         return dst;
339 }
340
341 static int fetch_response_reader(void *data, const char *block, size_t len)
342 {
343         struct ast_str **response = data;
344         unsigned char *tmp;
345
346         if (!(tmp = ast_malloc(len + 1))) {
347                 return -1;
348         }
349         memcpy(tmp, block, len);
350         tmp[len] = '\0';
351         ast_str_append(response, 0, "%s", tmp);
352         ast_free(tmp);
353
354         return 0;
355 }
356
357 static int auth_credentials(void *userdata, const char *realm, int attempts, char *username, char *secret)
358 {
359         struct exchangecal_pvt *pvt = userdata;
360
361         if (attempts > 1) {
362                 ast_log(LOG_WARNING, "Invalid username or password for Exchange calendar '%s'\n", pvt->owner->name);
363                 return -1;
364         }
365
366         ne_strnzcpy(username, pvt->user, NE_ABUFSIZ);
367         ne_strnzcpy(secret, pvt->secret, NE_ABUFSIZ);
368
369         return 0;
370 }
371
372 static struct ast_str *exchangecal_request(struct exchangecal_pvt *pvt, const char *method, struct ast_str *req_body, struct ast_str *subdir)
373 {
374         struct ast_str *response;
375         ne_request *req;
376         int ret;
377         char buf[1000];
378
379         if (!pvt) {
380                 ast_log(LOG_ERROR, "There is no private!\n");
381                 return NULL;
382         }
383
384         if (!(response = ast_str_create(512))) {
385                 ast_log(LOG_ERROR, "Could not allocate memory for response.\n");
386                 return NULL;
387         }
388
389         snprintf(buf, sizeof(buf), "%s%s", pvt->uri.path, subdir ? ast_str_buffer(subdir) : "");
390
391         req = ne_request_create(pvt->session, method, buf);
392         ne_add_response_body_reader(req, ne_accept_2xx, fetch_response_reader, &response);
393         ne_set_request_body_buffer(req, ast_str_buffer(req_body), ast_str_strlen(req_body));
394         ne_add_request_header(req, "Content-type", "text/xml");
395
396         ret = ne_request_dispatch(req);
397         ne_request_destroy(req);
398
399         if (ret != NE_OK || !ast_str_strlen(response)) {
400                 ast_log(LOG_WARNING, "Unknown response to CalDAV calendar %s, request %s to %s: %s\n", pvt->owner->name, method, pvt->url, ne_get_error(pvt->session));
401                 ast_free(response);
402                 return NULL;
403         }
404
405         return response;
406 }
407
408 static int exchangecal_write_event(struct ast_calendar_event *event)
409 {
410         struct ast_str *body = NULL;
411         struct ast_str *response = NULL;
412         struct ast_str *subdir = NULL;
413         struct ast_str *uid = NULL;
414         struct ast_str *summary = NULL;
415         struct ast_str *description = NULL;
416         struct ast_str *organizer = NULL;
417         struct ast_str *location = NULL;
418         struct ast_str *start = NULL;
419         struct ast_str *end = NULL;
420         struct ast_str *busystate = NULL;
421         int ret = -1;
422
423         if (!event) {
424                 ast_log(LOG_WARNING, "No event passed!\n");
425                 return -1;
426         }
427
428         if (!(event->start && event->end)) {
429                 ast_log(LOG_WARNING, "The event must contain a start and an end\n");
430                 return -1;
431         }
432         if (!(body = ast_str_create(512)) ||
433                 !(subdir = ast_str_create(32))) {
434                 ast_log(LOG_ERROR, "Could not allocate memory for request!\n");
435                 goto write_cleanup;
436         }
437
438         if (!(uid = ast_str_create(AST_UUID_STR_LEN)) ||
439                 !(summary = ast_str_create(32)) ||
440                 !(description = ast_str_create(32)) ||
441                 !(organizer = ast_str_create(32)) ||
442                 !(location = ast_str_create(32)) ||
443                 !(start = ast_str_create(32)) ||
444                 !(end = ast_str_create(32)) ||
445                 !(busystate = ast_str_create(32))) {
446                 ast_log(LOG_ERROR, "Unable to allocate memory for request values\n");
447                 goto write_cleanup;
448         }
449
450         if (ast_strlen_zero(event->uid)) {
451                 uid = generate_exchange_uuid(uid);
452         } else {
453                 ast_str_set(&uid, AST_UUID_STR_LEN, "%s", event->uid);
454         }
455
456         if (!is_valid_uuid(uid)) {
457                 ast_log(LOG_WARNING, "An invalid uid was provided, you may leave this field blank to have one generated for you\n");
458                 goto write_cleanup;
459         }
460
461         summary = xml_encode_str(summary, event->summary);
462         description = xml_encode_str(description, event->description);
463         organizer = xml_encode_str(organizer, event->organizer);
464         location = xml_encode_str(location, event->location);
465         start = epoch_to_exchange_time(start, event->start);
466         end = epoch_to_exchange_time(end, event->end);
467         busystate = bs_to_exchange_bs(busystate, event->busy_state);
468
469         ast_str_append(&body, 0,
470                 "<?xml version=\"1.0\"?>\n"
471                 "<a:propertyupdate\n"
472                 "  xmlns:a=\"DAV:\"\n"
473                 "  xmlns:e=\"http://schemas.microsoft.com/exchange/\"\n"
474                 "  xmlns:mapi=\"http://schemas.microsoft.com/mapi/\"\n"
475                 "  xmlns:mapit=\"http://schemas.microsoft.com/mapi/proptag/\"\n"
476                 "  xmlns:x=\"xml:\" xmlns:cal=\"urn:schemas:calendar:\"\n"
477                 "  xmlns:dt=\"uuid:%s/\"\n" /* uid */
478                 "  xmlns:header=\"urn:schemas:mailheader:\"\n"
479                 "  xmlns:mail=\"urn:schemas:httpmail:\"\n"
480                 ">\n"
481                 "    <a:set>\n"
482                 "      <a:prop>\n"
483                 "        <a:contentclass>urn:content-classes:appointment</a:contentclass>\n"
484                 "        <e:outlookmessageclass>IPM.Appointment</e:outlookmessageclass>\n"
485                 "        <mail:subject>%s</mail:subject>\n" /* summary */
486                 "        <mail:description>%s</mail:description>\n" /* description */
487                 "        <header:to>%s</header:to>\n" /* organizer */
488                 "        <cal:location>%s</cal:location>\n" /* location */
489                 "        <cal:dtstart dt:dt=\"dateTime.tz\">%s</cal:dtstart>\n" /* start */
490                 "        <cal:dtend dt:dt=\"dateTime.tz\">%s</cal:dtend>\n" /* end */
491                 "        <cal:instancetype dt:dt=\"int\">0</cal:instancetype>\n"
492                 "        <cal:busystatus>%s</cal:busystatus>\n" /* busy_state (BUSY, FREE, BUSY_TENTATIVE) */
493                 "        <cal:meetingstatus>CONFIRMED</cal:meetingstatus>\n"
494                 "        <cal:alldayevent dt:dt=\"boolean\">0</cal:alldayevent>\n" /* XXX need to add event support for all day events */
495                 "        <cal:responserequested dt:dt=\"boolean\">0</cal:responserequested>\n"
496                 "        <mapi:finvited dt:dt=\"boolean\">1</mapi:finvited>\n"
497                 "      </a:prop>\n"
498                 "    </a:set>\n"
499                 "</a:propertyupdate>\n",
500                 ast_str_buffer(uid),
501                 ast_str_buffer(summary),
502                 ast_str_buffer(description),
503                 ast_str_buffer(organizer),
504                 ast_str_buffer(location),
505                 ast_str_buffer(start),
506                 ast_str_buffer(end),
507                 ast_str_buffer(busystate));
508         ast_verb(0, "\n\n%s\n\n", ast_str_buffer(body));
509         ast_str_set(&subdir, 0, "/Calendar/%s.eml", ast_str_buffer(uid));
510
511         if ((response = exchangecal_request(event->owner->tech_pvt, "PROPPATCH", body, subdir))) {
512                 ret = 0;
513         }
514
515 write_cleanup:
516         ast_free(uid);
517         ast_free(summary);
518         ast_free(description);
519         ast_free(organizer);
520         ast_free(location);
521         ast_free(start);
522         ast_free(end);
523         ast_free(busystate);
524         ast_free(body);
525         ast_free(response);
526         ast_free(subdir);
527
528         return ret;
529 }
530
531
532 static struct ast_str *exchangecal_get_events_between(struct exchangecal_pvt *pvt, time_t start_time, time_t end_time)
533 {
534         struct ast_str *body, *response;
535         char start[80], end[80];
536         struct timeval tv = {0,};
537         struct ast_tm tm;
538
539         tv.tv_sec = start_time;
540         ast_localtime(&tv, &tm, "UTC");
541         ast_strftime(start, sizeof(start), "%Y/%m/%d %T", &tm);
542
543         tv.tv_sec = end_time;
544         ast_localtime(&tv, &tm, "UTC");
545         ast_strftime(end, sizeof(end), "%Y/%m/%d %T", &tm);
546
547         if (!(body = ast_str_create(512))) {
548                 ast_log(LOG_ERROR, "Could not allocate memory for body of request!\n");
549                 return NULL;
550         }
551
552         ast_str_append(&body, 0,
553                 "<?xml version=\"1.0\"?>\n"
554                 "<g:searchrequest xmlns:g=\"DAV:\">\n"
555                 "        <g:sql> SELECT \"urn:schemas:calendar:location\", \"urn:schemas:httpmail:subject\",\n"
556                 "                \"urn:schemas:calendar:dtstart\", \"urn:schemas:calendar:dtend\",\n"
557                 "                \"urn:schemas:calendar:busystatus\", \"urn:schemas:calendar:instancetype\",\n"
558                 "                \"urn:schemas:calendar:uid\", \"urn:schemas:httpmail:textdescription\",\n"
559                 "                \"urn:schemas:calendar:organizer\", \"urn:schemas:calendar:reminderoffset\"\n"
560                 "                FROM Scope('SHALLOW TRAVERSAL OF \"%s/Calendar\"')\n"
561                 "                WHERE NOT \"urn:schemas:calendar:instancetype\" = 1\n"
562                 "                AND \"DAV:contentclass\" = 'urn:content-classes:appointment'\n"
563                 "                AND NOT (\"urn:schemas:calendar:dtend\" &lt; '%s'\n"
564                 "                OR \"urn:schemas:calendar:dtstart\" &gt; '%s')\n"
565                 "                ORDER BY \"urn:schemas:calendar:dtstart\" ASC\n"
566                 "         </g:sql>\n"
567                 "</g:searchrequest>\n", pvt->url, start, end);
568
569         ast_debug(5, "Request:\n%s\n", ast_str_buffer(body));
570         response = exchangecal_request(pvt, "SEARCH", body, NULL);
571         ast_debug(5, "Response:\n%s\n", ast_str_buffer(response));
572         ast_free(body);
573
574         return response;
575 }
576
577 static int update_exchangecal(struct exchangecal_pvt *pvt)
578 {
579         struct xmlstate state;
580         struct timeval now = ast_tvnow();
581         time_t start, end;
582         struct ast_str *response;
583         iksparser *p;
584
585         state.pvt = pvt;
586         start = now.tv_sec;
587         end = now.tv_sec + 60 * pvt->owner->timeframe;
588         if (!(response = exchangecal_get_events_between(pvt, start, end))) {
589                 return -1;
590         }
591
592         p = iks_sax_new(&state, parse_tag, parse_cdata);
593         iks_parse(p, ast_str_buffer(response), ast_str_strlen(response), 1);
594         ast_calendar_merge_events(pvt->owner, pvt->events);
595         ast_free(response);
596
597         return 0;
598 }
599
600 static void *exchangecal_load_calendar(void *void_data)
601 {
602         struct exchangecal_pvt *pvt;
603         const struct ast_config *cfg;
604         struct ast_variable *v;
605         struct ast_calendar *cal = void_data;
606         ast_mutex_t refreshlock;
607
608         if (!(cal && (cfg = ast_calendar_config_acquire()))) {
609                 ast_log(LOG_ERROR, "You must enable calendar support for res_exchangecal to load\n");
610                 return NULL;
611         }
612
613         if (ao2_trylock(cal)) {
614                 if (cal->unloading) {
615                         ast_log(LOG_WARNING, "Unloading module, load_calendar cancelled.\n");
616                 } else {
617                         ast_log(LOG_WARNING, "Could not lock calendar, aborting!\n");
618                 }
619                 ast_calendar_config_release();
620                 return NULL;
621         }
622
623         if (!(pvt = ao2_alloc(sizeof(*pvt), exchangecal_destructor))) {
624                 ast_log(LOG_ERROR, "Could not allocate exchangecal_pvt structure for calendar: %s\n", cal->name);
625                 ast_calendar_config_release();
626                 return NULL;
627         }
628
629         pvt->owner = cal;
630
631         if (!(pvt->events = ast_calendar_event_container_alloc())) {
632                 ast_log(LOG_ERROR, "Could not allocate space for fetching events for calendar: %s\n", cal->name);
633                 pvt = unref_exchangecal(pvt);
634                 ao2_unlock(cal);
635                 ast_calendar_config_release();
636                 return NULL;
637         }
638
639         if (ast_string_field_init(pvt, 32)) {
640                 ast_log(LOG_ERROR, "Couldn't allocate string field space for calendar: %s\n", cal->name);
641                 pvt = unref_exchangecal(pvt);
642                 ao2_unlock(cal);
643                 ast_calendar_config_release();
644                 return NULL;
645         }
646
647         for (v = ast_variable_browse(cfg, cal->name); v; v = v->next) {
648                 if (!strcasecmp(v->name, "url")) {
649                         ast_string_field_set(pvt, url, v->value);
650                 } else if (!strcasecmp(v->name, "user")) {
651                         ast_string_field_set(pvt, user, v->value);
652                 } else if (!strcasecmp(v->name, "secret")) {
653                         ast_string_field_set(pvt, secret, v->value);
654                 }
655         }
656
657         ast_calendar_config_release();
658
659         if (ast_strlen_zero(pvt->url)) {
660                 ast_log(LOG_WARNING, "No URL was specified for Exchange calendar '%s' - skipping.\n", cal->name);
661                 pvt = unref_exchangecal(pvt);
662                 ao2_unlock(cal);
663                 return NULL;
664         }
665
666         if (ne_uri_parse(pvt->url, &pvt->uri) || pvt->uri.host == NULL || pvt->uri.path == NULL) {
667                 ast_log(LOG_WARNING, "Could not parse url '%s' for Exchange calendar '%s' - skipping.\n", pvt->url, cal->name);
668                 pvt = unref_exchangecal(pvt);
669                 ao2_unlock(cal);
670                 return NULL;
671         }
672
673         if (pvt->uri.scheme == NULL) {
674                 pvt->uri.scheme = "http";
675         }
676
677         if (pvt->uri.port == 0) {
678                 pvt->uri.port = ne_uri_defaultport(pvt->uri.scheme);
679         }
680
681         pvt->session = ne_session_create(pvt->uri.scheme, pvt->uri.host, pvt->uri.port);
682         ne_redirect_register(pvt->session);
683         ne_set_server_auth(pvt->session, auth_credentials, pvt);
684         if (!strcasecmp(pvt->uri.scheme, "https")) {
685                 ne_ssl_trust_default_ca(pvt->session);
686         }
687
688         cal->tech_pvt = pvt;
689
690         ast_mutex_init(&refreshlock);
691
692         /* Load it the first time */
693         update_exchangecal(pvt);
694
695         ao2_unlock(cal);
696
697         /* The only writing from another thread will be if unload is true */
698         for (;;) {
699                 struct timeval tv = ast_tvnow();
700                 struct timespec ts = {0,};
701
702                 ts.tv_sec = tv.tv_sec + (60 * pvt->owner->refresh);
703
704                 ast_mutex_lock(&refreshlock);
705                 while (!pvt->owner->unloading) {
706                         if (ast_cond_timedwait(&pvt->owner->unload, &refreshlock, &ts) == ETIMEDOUT) {
707                                 break;
708                         }
709                 }
710                 ast_mutex_unlock(&refreshlock);
711
712                 if (pvt->owner->unloading) {
713                         ast_debug(10, "Skipping refresh since we got a shutdown signal\n");
714                         return NULL;
715                 }
716
717                 ast_debug(10, "Refreshing after %d minute timeout\n", pvt->owner->refresh);
718
719                 update_exchangecal(pvt);
720         }
721
722         return NULL;
723 }
724
725 static int load_module(void)
726 {
727         ne_sock_init();
728         if (ast_calendar_register(&exchangecal_tech)) {
729                 ne_sock_exit();
730                 return AST_MODULE_LOAD_DECLINE;
731         }
732
733         return AST_MODULE_LOAD_SUCCESS;
734 }
735
736 static int unload_module(void)
737 {
738         ast_calendar_unregister(&exchangecal_tech);
739         ne_sock_exit();
740         return 0;
741 }
742
743 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "Asterisk MS Exchange Calendar Integration",
744                 .load = load_module,
745                 .unload = unload_module,
746                 .load_pri = AST_MODPRI_DEVSTATE_PLUGIN,
747         );